Poorer Outcomes among HIV Patients on Public Insurance

Among HIV positive people who started antiretroviral therapy in the U.S. HOPS cohort, those who used public insurance such as Medicare or ADAP had more cardiovascular and liver disease and were more likely to die than individuals with private insurance, according to a report in the August 5, 2011, advance online edition of AIDS.

Frank Palella and colleagues with the HIV Outpatient Study (HOPS) looked at mortality rates, causes of death, and associated factors among participants in this large prospective observational cohort, which included HIV positive people receiving care between 1996 and 2007 at 12 sites in Chicago, Denver, Oakland (CA), Philadelphia, San Leandro (outer San Francisco Bay Area), Stony Brook (Long Island, NY), Tampa, and Washington, DC

The analysis included 3754 HOPS participants with more than 6 months of follow-up after starting highly active antiretroviral therapy (HAART); this group was classified as "substantially treated," meaning they were under observation at least 75% of their time on therapy. The median duration of follow-up was 4.7 years.

Most participants (84%) were men, the median age was 39 years, 60% were white, 29% were black, and 12% were Hispanic/Latino. The median CD4 T-cell count at study entry was 295 cells/mm³, with a nadir (lowest-ever count) of 180 cells/mm³. About two-thirds had an AIDS diagnosis. About half reported smoking and 10% had a history of injection drug use.

More than half (57%) had private insurance and one-third (32%) had public insurance including Medicare (which provides care for low-income people), Medicaid (for people over 65 and some disabled individuals), and Ryan White Care Act/AIDS Drug Assistance Program (ADAP) funding.

The researchers looked at outcomes including death and its causes in relation to demographic factors, HIV disease status, and whether participants had private or public insurance; this analysis included 3569 participants, excluding individuals with unknown source of coverage or care paid for by the trial.

Results

• Substantially treated participants experienced a total of 331 deaths during follow-up (1.6 per 100 person-years).
• In a multivariate analysis, higher mortality was significantly associated with the following factors:
  • Pre-treatment CD4 cell count < 200 cells/mm³ (adjusted hazard ratio [aHR] 2.86);
  • Older age (aHR 1.50 per 10 years);
  • HIV RNA viral load (aHR 1.67 per log).
• Mortality did not differ significantly, however, according to race/ethnicity (aHR 0.99 for blacks vs whites).
• Mortality was significantly higher among participants with public insurance compared with those who were privately insured if pre-treatment CD4 count was > 200 cells/mm³ (aHR 2.03)
• This was not the case, however, among people with AIDS who had < 200 cells/mm³ when starting ART (aHR 1.3).
• People with public insurance had twice as many deaths due to cardiovascular events (30% vs 15%) and liver disease (24% vs 12%) than those with private insurance.
• Co-morbidities seen more frequent among deceased participants with public versus private insurance included cardiovascular disease (25% vs 13%), chronic hepatitis B or C (48% vs 18%), and kidney impairment (26% vs 13%).
• Among participants with CD4 counts above 200 cells/mm³, people with public insurance had significantly higher rates of high blood pressure (35% vs 19%), viral hepatitis (29% vs 9%), diabetes (7% vs 2%), and chronic obstructive pulmonary disease (6% vs 1%).

Based on these findings, the study authors concluded, "Among HAART treated participants with CD4 > 200 cells/mm³, [publicly insured patients] experienced higher death rates than [privately insured patients]."

"Non-AIDS death and disease causes predominated among publicly insured decedents, suggesting that treatable comorbidities contributed to survival disparities," they added.

This study does not indicate that publicly insured patients necessarily receive inferior care, the researchers elaborated in their discussion, but rather that "the population of persons whose access to healthcare was principally through public sources was significantly enriched in patients diagnosed with comorbidities -- usually treatable and often preventable -- that are known to be causes of the diseases that predominated as causes of death."

"As our nation undergoes healthcare reform, we need to better understand how healthcare delivery and its financial reimbursement affect quality of care (including routine well-health screening and pre-emptive care) and mortality risk, particularly among groups of persons who have higher prevalence of illnesses that ultimately contribute to mortality regardless of insurance status," they wrote. "In the interim, screening for and addressing modifiable health risks associated with preventable and treatable medical conditions should guide clinical practice and inform public health measures in our efforts to further improve survival and enhance overall health for all patients."

Investigator affiliations: Northwestern University, Chicago, IL; Cerner Corporation, Vienna, VA; Centers for Disease Control and Prevention, Atlanta, GA; Temple University, Philadelphia, PA; University of Illinois, Chicago, IL.

9/9/11

Reference

FJ Palella, RK Baker, K Buchacz, et al (HOPS Investigators). Increased Mortality among Publicly Insured Participants in the HIV Outpatient Study (HOPS) Despite HAART Treatment. AIDS (abstract). August 5, 2011 (Epub ahead of print).